So I have been reading a bit of stuff by Darren Doherty and his design process. He’s got photos on his site and Facebook pages that show step by step how they do their planning. So I took that and added it into what I’ve already read and re-jigged the layouts. This set of images shows the whole farm layout.

Base Map
The base map of the farm, with topographic lines at 0.5m. High points are on the south west corner.
Subdivision (Homestead Removed)
The red area marks the subdivision of the original homestead, it is a separate title.

This time instead of hunting around for a sweetspot or keyline I put in some ponds in small subtle valley shapes. Then I wiggled them up or down slope in order to connect them together with one continuous graded distribution swale at a 1% slope. I found five spots that should work for the smaller sized ponds we can build in our area without permits and paperwork. I haven’t settled on final depth/size, at the moment I have them between 800 cubic metres and 1800 cubic metres in volume. They range from 3-4 metres deep, and I may push them deeper and the sizes out on the smaller ponds. I should have more than enough water to fill the bigger ponds each year, the set should fill to 70% capacity with the spring melt.

Catchment Ponds
Ponds fed by catchments and placed as high up on the property as possible and still fill.
Main Distribution Swale
This is the main distribution swale, it slopes at 1% from the west towards pond P5, and in from the south towards P5. Arrows show flow direction.

I then marked out the rough irrigation system. I put in two cisterns on the centre high ridge that are fed by pumps from the ponds. In a pinch I can have the pumps fill the distribution swale to flow into the next pond down the line. From the cisterns come the web of lines for gravity fed water. I should be getting 20psi down in the lower areas of the farm, and enough flow to keep livestock watered. Next I put in the main access roads for the farm, running it parallel to the distribution swale and using it as part of the water collection system.

Irrigation Lines
This maps out the rough irrigation lines (probably 2″ poly pipes, trenched). Dark blue dashed lines are pumped, light blue gravity fed.
Roads
The dark gray road is the main farm road, it gets us within 200 meters of most of the farm. The light grey roads get us to the rest of the area, and run along ridges.

Based on the roads, existing trees and wild spaces as well as the irrigation features I marked out preliminary permanent fence lines. Between the roads and the fences it seems to make a tidy set of permanent paddocks/zones to work with for grazing and tree crop production.

Permanent Fence Lines
Red dashed lines are the permanent fence lines, breaking the farm up into eight paddocks/zones.

Around the entire road system I’ve put in a belt of trees to be used for fuel wood and biofuels; a mix of willow, manitoba maple, and green ash. The belts will be coppiced on a mixed rotation, with our rainfall it should work out to 7 years for willow, 10 years for manitoba maple, and 15 years for green ash. The willow will burn out in 50-70 years needing replacements, while the maple and ash should last around 100-120 years. I went with this mix because I think it should hold up best to our weather patterns, especially the chinook winds. I also have a thing for green ash, if we wanted we could leave standards in the mix or grow them longer for marketable coppiced timber on a 30-45 year cycle. All three species are easy self seeders and we should have no issues starting new trees on the farm for replacements.

The belts are on both sides of the road and will double as wind breaks and snow drift catchers. Since they aren’t terribly far apart the double row should function like a single windbreak, and the road should stay drift free for the most part, while the windward and leeward sides build drifts. In total it works out to 4.25 acres of trees and should provide about 5 metric tons of fuel wood per year.

Road Tree Belts
The green areas mark out a mix of willow, manitoba maple, and green ash trees that double as coppice firewood and wind breaks.

Around the core structure of the farm I added headlands (or head space) so tractors and other equipment/livestock can get in and about. Since we don’t currently have a tractor I based it on double the turning radius of a mid sized Kubota, which should let contract hay crews in to work. We’d probably never have anything larger than a mid sized Kubota for our own use.

Head Space
Head space for equipment and critters.

In walking the farm and talking with previous owners and the current renter I think I’ve found an area that should work for the building site for the farm and outbuildings. It’s off to the side of the old homestead and acreage, and gets what I think is the best compromise between ideal land placement, ease of access in and out, ease of access to the rest of the farm, and aesthetics.

Once I had all these elements in I calculated the catchment area and water potential for spring melt, yearly rainfall, and a 100 year rain event in our area (100mm in 24 hours). Everything should hold up fine for filling the dugout ponds to capacity by the end of our wet season (June). On a 100 year rainfall it has the potential to overload the system if we’ve had a decent spring melt, so the final pond in the chain (P5) will need a good spillway to keep things from blowing out. I might consider putting in an extension on the distribution swale to move overflow gracefully to the big pond on the north east corner of the farm. Later I will double check that our swale system and vernal ponds add in enough buffer capacity to minimize a 100 year rain event.

Farm Yard Site
Proposed farm yard site.
Catchments
Catchments, naming (A1-5) corresponds to the dugout pond it fills (P1-5).

In each of the paddock zones I pulled out a keyline and set up swales on a 1% grade towards ridge land forms, then gently fudged them on or off keyline to get nice swale shapes. I was a lot less anal in this round, figuring close enough was good enough. There are a couple areas where water may not flow in an ideal pattern, but it should get 90% of the water to slowly drift from valleys to ridges in a non-erosive way.

I’ve left vernal capacity expansion ponds out for the moment, and will come back in with some catchment math to make sure I’m not sitting on endless blowouts for the swale system.

The swales are 45-50 meters apart. In our area this gives the pasture 30-50% shade during our hottest and driest months (July, August, September) and should give our pasture a longer growing and green period. Down side is it might delay green up by a couple weeks in the spring if the trees decide to leaf out early. I think I’ll take the green grass in September as a fair trade.

Keyline Pattern Swales
Swales are 50cm wide and 50cm deep, give or take, with check dams every 10m to make sure the water moves nice and slow.

On the downslope side of each swale will go some form of tree crops. I have not decided on the final mix, but if I can get chestnuts and walnuts or butternuts to survive in the chinook zone we’ll do a mix of hazelnuts, chestnuts, and walnuts as the core of our tree crops. Secondary tree crops/understory will be apples, pears, cherries, and apricots. Cane berries and shrub berries do well in our area, so those will be put in as the edging/lowest tier in places. Grape vines might survive the chinooks, if they do they will get trellised on trees.

If the taller nut trees don’t work out or the genetics are looking like they will take decades to push for our climate we’ll switch over to a timber wood crop like ash mixed with korean pine for pine nuts (and blueberry habitat).

The trees will act as wind breaks and drift catchers. I’ve got a small obsession with snow drifts since we get a fair bit of wind in the winter and a good 1/3 of our precipitation is snow. If I can snag more of it on the farm, and any blowing in from the neighbours, I will. Plus I have these super nice snowshoes… All told it works out to about 7.5 acres of trees.

Swale Tree Belts
Belts of trees on the down slope side of the keyline swales. The aim is for them to be food producing trees, with timber secondary.

So that seems to be the general core layout of the farm for now. I am starting to work on perennial based crops that we can integrate into the system as well as the pasture. I’m thinking asparagus, ramps, walking onion, hazelnuts, fiddlehead ferns, and berries will end up in there. It really depends on how livestock heavy we want to get and how much labour we can handle. For annuals I may consider putting in some safflower or sunflower for bio diesel for the tractors, the only issue is that at -20C (common here) those oils become rock solid and won’t flow. I’m thinking steam powered using hazelnut husks and fuel wood might be better.

As usual feed back would be awesome!

2 thoughts to “Unravelling Keyline, Part 4

  • AndrĂ© Lemos

    Hi Marcus. thanks for your step by step thinking process, it helped me because i was feeling kind of stupid as to not been solving the problem but now i will wait for the light to appear đŸ™‚
    I have a 7 ha farm and i am trying to make a keyline design but stilll haven’t had that ah ah moment! đŸ™‚

    I ended up making parallel lines starting on one ridge, crossing the valley and ending on the other ridge. The problem i am facing with is that the end points on the second ridge are higher than the valley point (this above the keypoint)…
    if i understood it right, you had the same design problem.

    Take care,
    André

    Reply
    • Marcus Riedner

      Yes. In that case if you are doing strict keyline design you start a new pattern as I understand it.

      Reply

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